Sorry that there is no paging component in SmartGWT. But some good guy wrote a component called GridPager that could satisfy your requirements, I think.
GridPager should work with ListGrid.
You can find component information on googling.
There is also a discussion about the SmartGWT paging feature, I think it helps. URL http://forums.smartclient.com/showthread.php?t=3103
The discussion also mentions GridPager.
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